TRENTON – It’s an immutable fact of political life: Elected officials will use their office to further their politics. But while it is against the law for an official’s staff to use government time to campaign for their boss, where exactly is the line that separates governing from electioneering?

That was the recurring theme of the Legislature’s investigative committee last week as it continued its probe of the George Washington Bridge lane closures and Gov. Chris Christie’s quest for re-election last year.

Staffers in Christie’s since-eliminated Office of Legislative and Governmental Affairs would discuss, during off hours, political endorsements with the same mayors they spoke with during government business hours. There was a list of key towns, an expectation for staffers to use personal email accounts for political activity and an informal understanding not to reach out to mayors who had fallen out of political favor.

Assemblyman John Wisniewski, D-Middlesex, said Tuesday’s testimony by former director of departmental relations Christina Genovese Renna reinforced the perception that the office, referred to as IGA, was election-focused.

“There was trouble in getting specific delineation, if you will, about where the campaign stopped and government started,” Wisniewski said.

Wisniewski said, for example, that an email was sent to Renna at 9:30 a.m. one day about a list of potential mayoral endorsements. Renna didn’t send the email, but people from the outside had no qualms about sending political emails at a time she was clearly on the government clock.

“Even if you were to give the most liberal interpretation to her testimony, certainly that says there were people who were feeding into IGA direction about potential targets, who was a likely subject of an endorsement, and that’s troubling in and of itself,” Wisniewski said.

Questions about the blurred lines between governing and campaigning could prove relevant as the Legislature’s investigative committee tries to determine why the George Washington Bridge access lanes suddenly were rerouted last September and whether it was done or even could have been done for a political reason such as Democratic Fort Lee Mayor Mark Sokolich’s unwillingness to endorse Christie.

Renna defended the work done by the IGA, saying that outside of the bridge closures — apparently put into motion through an email from the office’s former deputy chief of staff, Bridget Kelly — the office was focused on good-government efforts and connecting the state’s executive branch with local elected officials and lawmakers.

It also employed some of Christie’s most politically active aides.

For its first three years, it had been run by William Stepien, who managed Christie’s 2009 and 2013 campaigns. He was replaced by Kelly, who had worked on the 2009 campaign. Its directors and regional directors have gone on to direct the Republican state parties in New Hampshire and New Jersey.

IGA’s regional directors were told in January 2013 to begin soliciting endorsements from Democratic mayors, and deputy chief counsel Paul Matey authorized the effort so long as it was done after hours, says an internal report done by the Gibson, Dunn & Crutcher law firm that Christie’s office commissioned.

Starting in the summer, IGA staffers headed to Christie campaign headquarters for “Bridgewater Wednesdays” each week, when they would make phone calls to prospective voters. Each Saturday, IGA staffers took part in conference calls with campaign staff. Bridgewater is the county seat of Somerset County.

The Gibson Dunn summary of its interview with Richard Rebisz, a superstorm Sandy-focused regional director in Christie’s office, said Rebisz assumed Kelly’s decisions and orders were coming from Stepien.

“Rebisz recalled that Kelly would say that she had to check with ‘Bridgewater’— meaning the campaign or Stepien — before approving certain things,” the report states.

Christie, at a news conference April 29, said he didn’t think IGA staffers had done campaign work on government time and that “those lines were fairly clear” about what wasn’t allowed.

“I don’t personally watch every person every minute of every day here, but clear instructions were sent throughout the administration that if you want to volunteer time for our campaign or for any other campaign that was going on out there, that it had to be done during your free time,” Christie said. “If someone was doing that, they were doing it without authority.”

The Gibson Dunn internal report says chief counsel Charles McKenna and chief of staff Kevin O’Dowd “were very focused on maintaining the separation between the office and the campaign” and that McKenna made it clear it should be taken seriously.

New Jersey’s ethics law doesn’t prohibit employees from actively campaigning for candidates seeking public office. But it says there are no circumstances under which an employee can use state time or resources in pursuit of political activities — in legalese, public workers cannot “use official authority or influence that interferes with or affects the results of an election or a nomination for office.”

“A person holding a position in the career service or senior executive service shall not directly or indirectly use or seek to use the position to control or affect the political action of any person or engage in political activity during working hours,” state law reads.

The law doesn’t directly address the idea of capitalizing on a relationship forged though official work, such as liaison efforts with a mayor, to pursue an off-hours political endorsement.

“You can get around a lot of this stuff, if that’s your intent,” said Peggy Kerns, director of the Center for Ethics in Government at the National Conference of State Legislatures, a Washington-based champion of state lawmaking bodies. “There would be some concern about something like that, I would think. There’s the law and then there’s the spirit of the law, too, both of which have to be adhered to.”

Most states have lengthier sections of state law than New Jersey’s that outline permissible and prohibited political activity by public employees. A handful of states, such as Alabama, also include language that spells out that public workers have the same rights as other citizens to do campaign work, so long as it’s not on government time.

“Where states have tripped up on this, sometimes, is the accounting of the time, meaning that if an employee is off the state clock and is now on the campaign clock, this has to be documented and, again, resources can’t be used,” Kerns said.

“When you’re on your personal time, there aren’t a lot of taboos,” Kerns said. “If you work for a legislator, you wouldn’t want to go out after hours and campaign for somebody who’s running against him. That wouldn’t be illegal or unethical; it might just be stupid. But I don’t think there any states that say you can’t do campaign work on your personal time. That would have some constitutional problems.”